Abstract: A key-removable lock core of the same size as a standard core, to fit standard core receptacles, and having a key plug of improved pull resistance. The core body of figure-8 cross section has a key plug lobe which contains a sleeve having a core retainer lug movable by a control key between a projected core retaining position and a retracted core release position. A key plug having an enlarged rear head is inserted from the rear into the cylindrical bore defined by the sleeve, with the head overlapping the rear of both the sleeve and the key plug lobe of the body. A segment is inserted in a slot traversing the key slot and is trapped therein by the sleeve to form a key stop. The key plug is held in place by a C-shaped retaining ring in a circumferential groove in such plug at the front face of the body, and is trapped in place by a face plate fixed to the body by a blind annular rivet.

Abstract: Apparatus for providing a "hotel function" in a cylinder lock having a key-removable locking core in its outside knob. Actuation of a push button in the inside knob causes the core to be disabled from retracting the bolt and projects an indicator from the face of the outside knob. The key plug of the core is connected to rotate a throw member which is axially movable between an inward operative position and an outward disabling position. The throw member is connected to the roll-back cam by a flat blade slidable in a cross slot in the roll-back cam sleeve. In the operative position of the throw member, a full width section of the blade lies in the cross slot to clutch the blade to the roll-back cam, while in the disabling position, a narrowed section of the blade lies in the cross slot and is rotatable therein so as to declutch the blade from the roll-back cam.